Modified Project Summary/Abstract Section Project Summary Postpartum depression is one of the most pervasive types of psychopathology postpartum, with detrimental effects for both mothers and their infants. There are a limited number of non-pharmacological interventions at present, particularly interventions developed to reduce risk of postpartum depression in at-risk samples (e.g., women with a prior history of depression). Elucidating the mechanisms of action of efficacious treatments that reduce postpartum depression is critical, as it will facilitate understanding what mechanisms are engaged and how intervention during pregnancy can optimize engagement of these mechanisms. This pilot translational fMRI study proposes to examine whether cognitive control and emotion regulation are potential mechanisms of action during the postpartum period, both at the behavioral and neural level, of Mindfulness-Based Cognitive Therapy ? Perinatal Depression (MBCT-PD). MBCT-PD is a group-based therapy that focuses on developing mindfulness and cognitive behavioral skills and has been shown to be efficacious in reducing depressive symptoms and emergence of major depressive disorder postpartum. Additionally, the study proposes to explore whether engagement of potential mechanisms of action effect intergenerational transmission of risk, namely reported negative infant emotionality.